Research Of Wireless Broadcast Transmission Algorithm Based On Network Coding

As a new technology, network coding has been going through rapid development in wireless networks and has changed the traditional pattern that intermediate nodes store and forward data packets by allowing intermediate nodes to encode the received data packets before forwarding them. Finally, the destination node restores the original packet according to the decoding packet that was received using coding coefficient. Existing studies show that the application of network coding techniques in wireless networks can significantly improve network robustness and reliability and reduce the total number of transmissions, thereby increasing the throughput of the network. Network coding in wireless networks has become a hot research topic. This paper aims to improve the efficiency of wireless transmissions by presenting studies pertaining to the reliability of broadcast retransmission algorithm and effective data broadcasting transmission algorithm of relieving broadcast storm based on network coding.Existing broadcasting retransmission methods can be divided into two categories:automatic repeat request (ARQ) and retransmission based on network coding. Though ARQ and retransmission based on network coding are comparable; ARQ is easier to obtain higher reliability. At present, the existing retransmission methods based on network coding obtain data packets from multiple retransmission packets and by weight flyers data packets to ensure the decoding possibilities in the terminal. However these existing retransmission methods don’t take into account errors and the loss of ACK and NAK. In order to improve the reliability of transmission in wireless networks, this paper presents the reliability of the broadcast retransmission algorithm based on network coding. The algorithm uses network coding techniques and the "polling feedback" mechanism which chooses a different end of packet loss in accordance with the importance of the packet at source and XOR encoding retransmitted packets. At last, the packets are recovered according to XOR by the retransmission packet and the data packets received before in terminal. When taking into account the ACK/NAK, the algorithm in process of packet retransmission is fully lost using the "polling feedback" mechanism based on NAK. NAK takes the initiative to obtain the packet loss information of the terminal to ensure the reliability of the radio. Data broadcasting is widely used but will cause broadcast storms and reduce the performance of a network. To avoid broadcast storms, the traditional method can be divided into probabilistic broadcast and clustering. In addition to the two programs above, network coding techniques can alleviate the broadcast storm effectively. This paper presents an effective data broadcasting transmission algorithm for relieving a broadcast storm based on network coding. The algorithm uses random linear network coding techniques and forwarding mechanism of coordination when sending packets which use linear encoded packets. This in turn can reduce the probability of packets being duplicated and improve the effectiveness of the node receiving a data packet; in addition, the node forwards the packet by a coordinated forwarding mechanism to suppress the broadcast storm for part of the node send data at the same time. This will reduce the redundancy, competition, and conflict in the broadcasting process. Through theoretical analysis and simulation results under typical channel that EDBTA algorithms suppress broadcast storms, while increasing the effectiveness of the data packet transmission.This paper uses NS2to build a simulation environment to simulate and analyze performance of the proposed algorithm to verify its effectiveness. The experimental results show that the proposed broadcast retransmission algorithm based on network coding RBRNC improves the reliability of the network and suppresses the broadcast storms transfer algorithm EDBTA to improve the effectiveness of suppressing broadcast storms.